Cold Sores

Cold sores are very common and quite contagious. Sometimes referred to as fever blisters, cold sores can be caused by the herpes simplex1 virus (HSV-1). They can appear as a single blister or cluster of them, often recurring in the same location, including on and around the lips, nose, chin or cheeks. Cold sores are often confused with canker sores, but canker sores are actually sores or ulcers that occur inside your mouth, and are not contagious. There are a number of treatment options available for this skin condition.

Recently Asked Questions

The Cold Sores .CA web site will help you understand the basics of cold sores, how it is diagnosed, the role of cold sores and how it relates to herpes, and which drugs are effective in treating them.

Cold Sores - The Basics

What Are Cold Sores?
Cold sores appear as a cluster of small blisters usually on the lips or around the mouth, especially the corners, and occasionally inside the nose. Approximately 20-40% of people will suffer a recurrent outbreak...

Why Do I Have Cold Sores?
Cold sores are caused by a virus. Once you have been exposed to the virus and infected with the herpes virus you are infected for life. Exposure to the HSV-1 virus and infection commonly occurs in childhood...

How Do I Know If I Have It?
Cold sores are most frequently located on the lips at the place where the lips meet the skin and the mucosa. This is known as the vermilion border. These herpes outbreaks can also be found occasionally on the cheek, chin and nose. In individuals who have their immune system suppressed by...

What Triggers Cold Sores?
Most of the time the outbreaks seem to have a life of their own and there is no one factor that appears to have initiated or caused the outbreak. There are a number of factors that are known to cause an outbreak of herpes labialis including...

What Are The Risks?
Proper hygiene is important at any time but especially during a cold sore outbreak. It is possible to transfer the virus from the cold sore around the mouth to other areas of the body causing an infection and sore in those places...

How To Confirm The Diagnosis?
The diagnosis is usually made by the history from the patient combined with the examination of the skin. At times it is difficult to be certain of the diagnosis...

Why and When to Treat
Cold sores can be uncomfortable, unsightly and embarrassing for sufferers and they also carry the risk of spreading the herpes virus to other parts of the body or to other people. The virus can be spread by the fingers or items such as...

Treatment and Medical Options

When You Have a Cold Sore
Do not squeeze, pinch, bite, or pick at blisters. Avoid eating acidic foods such as citrus fruits, tomatoes, pickles, or other foods such as salty snacks as they may sting and irritate the cold sore...

Medical Options
Most cold sores will clear up on their own after 7-10 days. Most treatment options are focused on reducing the discomfort and pain associated with cold sores and reducing the length of the outbreak. Some treatment options may even help prevent cold sore blisters from forming...

HSV-1 Infections

Diseases Caused by HSV
Herpes lesions can present on many parts of the body other than the mouth and genitalia, including the eye, fingers (herpetic whitlow), and torso or arms in athletes such as wrestlers (herpes gladiatorum). Eczema herpeticum is a particularly severe...

HSV-1 Primary Infection
Most primary infections with HSV-1 are asymptomatic (no apparent symptoms). However, primary infection can cause a variety of clinical symptoms such as infection of the mouth and gums...

Recurrent HSV-1 Infections
Approximately 20-40% of HSV-1 seropositive individuals will experience a reactivation of the virus. A common and well known sign of HSV-1 reactivation is the cold sore. Most individuals who suffer from recurrent cold sores will be aware of...